The 52-year-old reality star announced last month that she had checked herself into an alcohol treatment center after she was arrested in Palm Beach, Florida, on Christmas Eve for allegations of disorderly intoxication, resisting arrest and battery on a law enforcement officer. She pleaded not guilty.

"Luann's really a strong person. Before this, Luann [is] the most resilient person I know," Frankel tells ET. "She just is one of these people that can take a hit and keep on going. But, she is very humble and she's introspective and a little bit spiritual. I definitely think she's reevaluating a lot of things in her life, which is amazing. You don't [know] when someone comes out how they're going to handle it and describe it."

"So, we had a lot of good conversations. We were at a spa together. She's back in New York now, which was another sort of emersion, but she's taking it day by day," she continues. "I would not want to be condescending and say that I was proud of her, but I was impressed. I am impressed."

"I want to offer my most sincere apologies to anyone that I might have offended with my behavior. This was my first time in Palm Beach since my wedding and being here brought up buried emotions," de Lesseps wrote at the time. "I am committed to a transformative and hopeful 2018."

Last week, ET confirmed that de Lesseps was charged with the felony of resisting an officer with violence as well as misdemeanor charges of trespassing and disorderly intoxication. Her felony charge carries a possible sentence of up to five years, while the misdemeanors carry sentences of up to a year.

Meanwhile, Frankel also opened up to ET about working with Million Dollar Listing New York star Fredrik Eklund on their new show, Bethany & Fredrik.

"The best thing about Fredrik is that, he's a clown -- and it's hilarious," Frankel says. "He really is a clown, and I mean that in the nicest way. I am an idiot and I am attracted to other idiots, and so we could be in the biggest fight ever and we'd start laughing. I could cry right now. I peed my pants multiple times. I mean, we laughed."

"How hard did we laugh? We laughed so hard," she adds. "So, the most annoying thing about Fredrik? I'll be gentle. The most annoying thing about Fredrik is that he is a real estate broker and it is his job to always be selling. And [I'm] a little more direct and I don't like to sugarcoat things."